The safety and efficacy of specific sublingual immunotherapy for house dust mite allergens in patients over 60 years of age with allergic rhinitis and a confirmed allergy to house dust mites were the focus of the stu First, 111 patients, ages 60-75 years, with allergic rhinitis and with a confirmed allergy to D. pteronyssinus and D. farinae by the use of skin prick tests, serum-specific IgE and nasal provocation tests were included. Patients were individually randomised to groups: active or placebo using a double-blind method. A total of 51 subjects in the sublingual allergen-specific immunotherapy (SLIT) group (Staloral 300R, Stallergens, France) and 57 in the placebo group were monitored for three years. The patients had to record on a diary card whenever they used anti-allergic medications.